The invention relates to a frame arrangement for a vehicle roof that has a roof opening that can be closed by a cover panel, which is slidably and/or swingably displaceable to at least partially uncover the roof opening, and which is supported by a frame perimetrically bounding the roof opening. In particular, to such an arrangement wherein at least one guide element is disposed at each side of the cover panel and along which the cover panel is longitudinally slidable on tracks provided on side parts of the frame by a respective actuating cable that is guided in a cable channel and connected to an actuating device, and wherein a cover rail is used to form the cable guide channel and/or the tracks.
From German Offenlegungsschrift No. 35 32 103 and U.S. Pat. No. 4,749,227 frame arrangements for a vehicle roof of the above-mentioned type are known. In these known arrangements, the frame is provided with grooves that form a part of the cable guide channels. Connected to the frame, over these grooves constructed in the frame, is a cover rail which closes the open sides of the grooves to form cable guide channels that are closed on all sides. This cover rail extends beyond the grooves in the frame to form laterally running tracks for the guide element or elements of the cover in conjunction with an appropriate guide surface that is constructed on the frame. Also, in the case of the arrangement of German Offenlegungsschrift No. 35 32 103, at the transitions between the laterally provided cover rails and the separate front part misalignment unavoidably occurs, even if usually slight, between the grooves provided in the frame for the guide channels of the actuating cable, so that, because of this circumstance, a stiffness of the actuation and sometimes an undesirable production of noise may result. Furthermore, since these frame arrangements have the tracks and/or cable channels constructed directly in the frame, the frame must be provided together with the remainder of the assembly comprised of the cover and its drive components, i.e., cannot be a separate unit manufactured by a supplier to be applied to a frame separately produced by the vehicle manufacturer.
A vehicle roof is known from U.S. Pat. No. 4,293,161 that has a frame consisting of plastic which, on the one hand, has sliding surfaces for the guide elements or guide shoes for the cover panel and, on the other hand, guide channels for the actuating cable. Here also, the grooves in the frame partially define the guide channels for the actuating cable and are covered by covers which, simultaneously, form, on the side parts of the frame, a sliding surface for the guide shoes. In this case, essentially the same or similar difficulties occur as in the above-mentioned arrangements.
From U.S. Pat. No. 3,822,912, a cable drive and guide for a sliding cover panel of a vehicle roof is known, wherein a sheet metal part is fastened to the frame as a covering that forms, in conjunction with a suitably constructed profile of the frame and another sheet metal part fastened to the frame, a guide channel or channels for the actuating cable, and tracks for the guide elements of a suitable extension of the cover panel. Nothing is indicated as to the manner in which the actuating channels are guided at the front of the roof opening. With this configuration, at least three interacting parts are, thus, needed for the formation of the tracks and the cable channels, by which the assembly is made more difficult and production becomes more expensive, and since the guide channels for the actuating cables are defined at least in part by the frame, the construction of the frame must be adapted to the path of these guide channels.
In U.S. Pat. No. 4,332,416, a vehicle roof is disclosed in which the guide channels with the incorporated actuating cables and the tracks with the incorporated guide elements are combined into an installation unit which can be preassembled and which is then set into a frame perimetrically bounding the roof opening. Since this installation unit contains all the operational parts of the sliding roof (except for the frame), the operational testing can take place right before installation. However, in this arrangement there are, again, transition areas from the side parts to the front side that are subject to potential misalignment problems.